# DBT JRF 2022 — Question 63

Exam: DBT JRF 2022 · Section: B · Topic: Immunology › Vaccines & Malaria Immunology · Difficulty: Medium

## Question

RTS,S vaccine for malaria consists of the central repeat (R) region derived from Plasmodium falciparum circumsporozoite protein (CSP) that is genetically fused to the T-cell epitope (T) and surface antigen (S) regions derived from:

## Options

- **A.** Vaccinia virus
- **B.** Hepatitis B virus
- **C.** Adenovirus
- **D.** Influenza virus

## Answer

Option B

## Explanation

RTS,S malaria vaccine composition: RTS,S (Mosquirix, developed by GSK/PATH) is the first approved malaria vaccine: • R: Central repeat region of P. falciparum circumsporozoite protein (CSP) — NANP repeat units • T: T-cell epitope region of CSP (C-terminal) • S: HBsAg (Hepatitis B surface antigen) The entire R and T portions are fused to HBsAg (S = surface antigen), expressed in Saccharomyces cerevisiae (baker's yeast). The fusion protein self-assembles into virus-like particles (VLPs) that display the CSP epitopes in an immunogenic form. Adjuvant: AS01B (liposomes + MPL + QS21) dramatically enhances immune response. Efficacy: ~30–50% protection against clinical malaria in young children. Answer: RTS,S contains CSP repeat (R), T-cell epitope (T) fused to HBsAg (S), expressed in yeast.

Source: https://mypyqbuddy.com/questions/rts-s-vaccine-for-malaria-consists-of-the-6a104cd5920734408bc0c74e